Utilizing exhaust-steam



(No'gModel.) A

' D. RENSHAW.

UTILIZING EXE-AUST STEAM.

atented* July 19, 1881' lll-...

g UNITED STATES PATENT OFFICE.

DAVID RENSHAW, OF OOHASSET, ASSIGNOR OF ONE-HALF TO HARVEY T.

' LITOHFIELD, OF HULL, MASSACHUSETTS.

UTIL-IZING EXHAUST-STEAM.

SPECIFICATION ferming'pert ef Letters Patent Ne. 244,669, dated July 19, 1881.

Application tiled October 14, 18.80. (No model.)

To all whom it may concern: I

Be it known that I, DAVID RENsHAw, of Cohasset, in the county of Norfolk and State of Massachusetts, have invented a new and useful Improvementl in Utilizing Exhaust- Steam; and I do hereby declare that the following is a full, clear, and exact description of the invention, which will enable others skilled Iin the art to make and use the same.

My invention consists iu a process by means of which exhaust-steam can be returned to the boiler from which it emanated; and, further, in a device to assist said process. The process consists in taking steam from the boiler to a pump or equivalent device, then forcing said steam to a superheater, and then passing the Y superheated steam through-an injecting device,

into which the exhaust-steam enters in such a manner that the superheated steam will take up the exhaust-steam and throwit back to the boiler.

In the drawings, I have shown a boiler, A;

j an engine, E; a pump, B, worked by the boiler,

drawing steam from the boiler and forcing it to a superheater, C; and an injecting device, D, connected with the superheater, the exhauststeam pipes d-from the engine andpump, and with the boiler. Y A', A2, and A3 show the pipes supplying steam to the engine and pump, and A4 shows the pipe from the pump to the superheater.

Figures 1 and 2 show the general arrangement of the boiler, engine, pump, superheater, and injecting device; and Fig. 3 shows said device in detail.

The elements of this process consist in supplying the superheater with steam which can only act in one way upon the boiler, its backward pressure or kick being overcome by the check-valves of the pump, the pump acting on the boiler-steam as an air-pump aetson air.

It iswell known that when a boiler is connected with a superheater in the usual manner the pressure throughout the whole contents of the boiler and superheater is equal; and itis also well known that steam at a high pressure may be put into a boiler containing steam at a 10W pressure until both boilers have the same pressure. It is also well known that an air-pump will pump air-into a vessel to an almost 'indefinite extent of pressure.

This part of my invention is simply an airpump applied to steam, the piston for the working steam being larger than that for the steam to be pumped to the superheater, and its pumping force being regulated by the variation inthe diameters of said pistons. When the boiler-steam thus compressed by the pump into the chamber of the superheater is superheated, its pressure is increased, and it tends to force its way to the boiler with great velocity, and if not prevented by anycheck-valves it will take up the steam which is thrown oli` as exhaust, raise its temperature and force it back, to the boiler, the velocity and heat attained by said pumped and superheated steam being relied on for that purposae The pump B, which I have shown in the drawings, is a fly-wheel pump consisting of a pumping-engine, m, and a pump proper, n,f1t 7o ted with the requisite valves, and Having pistons connected .by a piston-rod, p, the stroke of the pistons being controlled by the conn ecting-rod s, which extends from `the pistonrod to the crank-shaft ofthe ily-wheel r.

The injecting device which I consider best for conducting the steam from the superheater to the boiler is shown in the drawings. `1t consists, mainly, of a frusto-conical chamber, a, from the apex of which a pipe, b, connects with the boiler, the pipe having a cock, c, to open or close, as required. Near the apex the exhaust-steampipe d enters the chamber, and opposite a pipe, e, leads from the chamber to conduct the exhaust-steam away, this latter 85 pipe being fitted with a cock, f, acting in opposition to the cockv leading from the boiler,

both being operated by one handle, w, so that when one is closed the other is open. The superheated steam enters a chamber, h, in the rear of the conical chamber a, and passes to a tubeft', (through openings k,) which extends to near the apex ofsaid conical chamber, its distance from the apex being made adjustable, as shown.

When the exhaust is to be passed away it is sent through the chamber a, entering the chamber through the pipe d, and passing from it through the pipe e, the cock c in this instance being closed and the cock f opened, both of these cocks being so constructed that when open there can be no obstruction to the body of steam passing through them.

When it is desired to force the exhaust to the boiler the superheated steam is passed through the tube to the chamber a, and the cocks c and f being reversed, a free passage is opened for the steam from the superlleater to drive the exhaust-steam back to the boiler, no obstruction in the way of check-valves or their equivalents being interposed.

I do not claim any particular boiler, superheater, or injecting device in connection With this process; but

1 claim as my invention, and desire to secure by Letters Patentl. The process for driving the exhaust-steam back to the boiler, consisting of pumping steam from a boiler into a superheater, there superheating said steam, and then using it to drive exhaust-steam back to the boiler through an injecting device, substantially as described.

2. In connection with a superheater supplied with steam from a pump, as described, the injecting device D,. consisting of a chamber, a, with entrance-piped' for the superheated steam, entrance-pipe d, and outlet-pipe e for the exhaust, and pipe b connecting said chamber a with the boiler, all as described and for the purpose specified.

DAVID RENSHAW.

Witnesses:

GHAs. F. SLEEPER, H. J. LITCHFIELD. 

